// When deleting an array, the dynamic and the static type of the object must be the same, or the behavior is undefined (C++ Standard 5.3.5/3).

struct X {
  int FOO;
  virtual ~X() { };
};

class Y : public X {
public:
  int BAR;
};

int main() {
  X *p = new Y[2];
  delete[] p;
  return 0;
}